The present invention relates generally to an improved design and construction of fitness training equipment wherein users can select the desired amount of weight from a stack of weight plates.
Selectable amount of weight is commonly found on various fitness training equipments. A popular method is by using a central stem going down the center holes of a stack of weight plates, wherein an insertion pin can be inserted through a hole on the side of each weight plate and through the central stem, forming the point of pick-up when users are engaging in exercising, as shown in FIG. 0. All the weight plates above the point of insertion pin will be the desired total weight. When users pull the cable, all the plates below the point of insertion pin will NOT be selected.
This type of popular weight selection system has at least three problems plaguing the industry:
a. The hole on the side of each weight plate has to match (be aligned) with the correspondent hole on the stem. Due to the accumulated thickness error of the weight plates, however, the top one or two holes on the weight plates oftentimes do not match up with the top one or two holes on the central stem. This poses a problem for users when insertion of the insertion pin is taking place at the top portion of the weight stack, unless the weight plates are machined to a very tight tolerance, which requires costlier production to achieve such precision.
b. When the central stem is lifted up, the bottom of the central stem will oftentimes have a lateral offset from the top of the remaining unselected weight stack, interrupting the smooth and successful of restoration of the central stem (insertion back down) into the weight stack, as the bottom tip of the stem will sometimes get suck on the surface of a weight stack, instead of going through the center hole of the weight plates.
c. Insertion pin gets lost easily. Even though insertion pins are tied to a cable, as many gyms customarily do it this way, some cables are cut to take away the insertion pins.
The present invention uses an up-down sliding block as the selection means, plus an additional belt-driven dial, to build on a link-connector system as disclosed in prior application, to solve the above-stated problems.